High pressure cold feeder pipe noise

Yes, I think you are on the right track.

If the new valve closes *too* fast, there is a possibility you could hear a "thump" or rattling. In that event, add an air chamber to the pipe, near the cistern to absorb the shock wave.

Jim

A few not very scientific tests later....

Fkushing the loo initially causes a racket. It then quickly quietens down. Then the racket then starts again and lasts much longer. Then quiet.

I suspect this can be explained by:

Water level drops as loo flushes Ballcock rapidly falls, opening valve fully While it is opening, we get noise Once fully open, peace and quiet As tank nears full again, valve starts to close Tank takes forever to fully fill, as valve closes further the close it gets Hence long drawn out noise

I'm guessing some clever person must have come up with a robust solution to this? The fluidmaster valves look like they might do (and also look very quiet - filling underwater), but look a bit plasticy and breakable...

A few not very scientific tests later....

Fkushing the loo initially causes a racket. It then quickly quietens down. Then the racket then starts again and lasts much longer. Then quiet.

I suspect this can be explained by:

Water level drops as loo flushes Ballcock rapidly falls, opening valve fully While it is opening, we get noise Once fully open, peace and quiet As tank nears full again, valve starts to close Tank takes forever to fully fill, as valve closes further the close it gets Hence long drawn out noise

I'm guessing some clever person must have come up with a robust solution to this? The fluidmaster valves look like they might do (and also look very quiet - filling underwater), but look a bit plasticy and breakable...

The FluidMaster has a good reputation on this side o' the pond :-)

Breakage really hasn't been a big problem.

For repairs (seldom needed) the top just pops off. Jim

Thanks -I'll give it a go. The council have the key to the loft, so I'll have to try to prise it off them... btw, which side of the pond is "this"?

Cheers,

Ben (UK)

"This" side is the western shore.

Cheers,

Jim (US)

On further consideration, I wonder if the FluidMaster will be large enough (i.e., flow-wise) to keep the cistern full under maximum draw. The cistern is common to all the tenants, right?

Also, with many demands for water, the FluidMaster might be switching On/Off rapidly, rather than gently modulating the flow as the ballcock is supposed to

Hmmmmmmm

Jim

That's a point. I'm not sure exactly how many people the tank serves, but I'll maybe have a chat with the local plumbers merchants. I don't think it can be the whole block (40 flats) as it doesn't fill regularly enough. I'd guess it's about 10 flats. I can't be the first person to have had this problem, and I can see no technical reason why a robust, large solution could not be produced. I suppose you could plum in a few in parallel (yuck, but should work!)

Ben